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This study aims to investigate the effect of the application of an ultrasound pretreatment on physicochemical, surface, thermal, and functional properties of two extracts from male date palm flowers. The obtained extracts were compared based on their structural and functional properties. It was proved that the application of sonication pretreatment has modified significantly (p <.05) the extract's characteristics. The protein yield, the essential amino acid content and the protein solubility were improved (29.61%, 29.22 g/100 g protein, and 91.1% for native sample against 35.26%, 41.04 g/100 g protein, and 100% for treated sample, respectively), while the protein content and the surfactant behavior at 1% were decreased due to the liberation of other compounds than protein. Moreover, the sonication has engendered some structural modifications such as the dissociation of some intermolecular bonds (FTIR) and the increase of crystalline region (X‐ray), which influenced the protein unfolding and have led to the decrease of enthalpy (DSC) (272.2 against 228.6 J/g) and the decrease of water‐holding capacity (11.62 against 9.51 g water/g of dry sample). Practical applications: The male date palm flowers (MDPF) present a rich matrix composed mainly of dietary fiber, protein, and minerals. The protein fraction of MDPF was considered as an excellent source of amino acids supplying the human requirements. The dietary fiber fraction was composed essentially of insoluble dietary fibers which contribute to a balanced diet by creating satiety feeling and facilitating the intestinal transit. The fibro‐proteic extract (FPE) of MDPF could be a potential functional ingredient for food applications. The physicochemical and functional properties of the FPE was changed by ultrasound pretreatment, which was beneficial to improve the protein yield, the amino acid profile, and the protein solubility. Nevertheless, both treated and non‐treated samples showed promising nutritional and functional characteristics that could be used in the food industry to ameliorate food quality. [ABSTRACT FROM AUTHOR]

This study aims to elucidate the effect of male date palm flower (MDPF) incorporation in the dough properties and biscuit characteristics. Farinograph analysis demonstrated a progressive increase in water absorption (56.85%–61%) and dough stability (1.88–20.25 min) with increasing MDPF quantity due to its wealth in dietary fiber. Biscuit formulations were prepared using 3, 6, and 9% MDPF powder and evaluated for their physico‐chemical, textural, and sensory properties. The results have shown a significant increase (p <.05) in dietary fiber (1.22%–84.81%), protein (7.64%–8.30%), and ash content (1.30%–1.68%) coupled with a darkness increase (77.30–58.52) compared to the control. The textural analysis of doughs and biscuits showed that hardness increased with the increase in MDPF incorporation levels (2.52–5.26 N and 11.32–15.64 N, respectively). The sensory evaluation showed that up to 9% MDPF incorporation, the different sensory attributes were positively correlated, with more appreciation for the 6% fortified‐biscuit. Owing to its nutritional value, the MDPF powder could be used as an ingredient for bakery food products in gastronomy. Practical applications: The male date palm flowers (MDPF) are considered as an under‐exploited by‐product as they are discarded or sometimes used in animal feed. However, they present a rich matrix composed mainly of dietary fiber, protein, and minerals. Nowadays, consumers are searching for healthy and novel foods which push the industrials to invent new dietetic formulations using vegetable protein source and dietary fibers. The MDPF incorporation in biscuit formulation might contribute to reducing these vegetable wastes allowing their valorization as a nutritional and functional ingredient at the same time. [ABSTRACT FROM AUTHOR]

The main objective was to investigate the effect of ultrasound‐assisted osmotic dehydration (UOD) pretreatment on the dehydration kinetics and the physicochemical properties of pomegranate seeds using a response surface methodology, in order to optimize the process. Quality attributes of seeds were estimated through the assessment of physical and thermal characteristics. Results showed a good correlation of experimental values with the model. The optimum conditions used for UOD and osmotic dehydration (OD) were found to be 240 min, 60°Brix, 41°C, and 240 min, 29°Brix, 50°C, respectively. UOD pretreatment led to a higher mass transfer rate than the OD process. UOD‐treated seeds reached the optimal moisture content (10%) and water activity (aw < 0.650) faster than both fresh seeds and OD‐treated seeds. Differential scanning calorimetry revealed that UOD pretreatment induced the loss of an important amount of water. X‐ray diffraction analysis showed that ultrasound pretreatment did not affect the amorphous characteristics of pomegranate seed powder during drying. Practical applications: Ultrasound‐assisted osmotic dehydration could be a novel approach for food preservation and processing, due to the combined effect of osmotic pressure gradient and ultrasonic effect on the surface of the food material. Ultrasound pretreatment can be implemented as an alternative pretreatment to reduce drying time and, consequently, processing costs. Ultrasound‐assisted osmotic dehydration is gradually gaining attention as a pretreatment method due to its advantages which include preservation of antioxidant properties and bioactive compounds. This study provides information on the application of response surface methodology for the optimization of ultrasound‐assisted osmotic dehydration of pomegranate seeds. [ABSTRACT FROM AUTHOR]

In this study, color values, amino acid, and sugar composition (sucrose, fructose, glucose, and maltose) of fresh and roasted sweet potatoes from 11 cultivars were determined. Sensory evaluation (overall acceptability), GC‐MS, electronic nose, and electronic tongue were also used to analyze the flavor compounds and sensory index. The results of overall acceptability indicated that Yanshu No. 25 and Pushu No. 32 were preferred to the other ones. Besides, there was a certain correlation between colors, sugars, amino acids, volatiles, and overall acceptability. However, maillard and other reactions during the roasting process of sweet potatoes are complicated, and the formation of characteristic flavor is more complex, which requires further research. Therefore, the results of this paper can provide theoretical basis for improving the quality characteristics of roasted sweet potatoes. Practical applications: The sensory characteristics of roasted sweet potatoes included color, aroma, and taste. However, there is little information about the effect of roasting on the quality of roasted sweet potatoes; no study has been conducted to investigate the effects of roasting on the changes in volatile compounds and sensory qualities of sweet potatoes, especially for different cultivars. The results of this study could illustrate which index was the most important factor that affected the overall acceptability of roasted sweet potatoes, and provided theoretical basis for improving the quality characteristics of roasted sweet potatoes, which could further promote the healthy development of roasted sweet potato industry. [ABSTRACT FROM AUTHOR]

This work aimed to evaluate the nutritional quality of a typical natural drink from male and female Deglet Nour (DN) date palm (Phoenix dactylifera L.) during the collection period. Dry matter, protein, amino acids, and sugar profiles were determined using AFNOR norm, Kjeldahl method, HPLC, and HPAEC-PAD, respectively. The male sap dry matter content was higher than that of the female. It decreased significantly through the tapping period. During the harvest, the male sap protein content decreased but increased significantly in the female sap. Finally, sugar fraction, for both male and female DN sap, was dominated by sucrose, glucose, fructose, and a small amount of myo-inositol. During the collection time, sugar content is affected by the sex especially for myo-inositol content that increased significantly in the female date sap, unlike that of the male one. This may be related to the fact that the male palm is more resistant to physiological stress, inducing myo-inositol formation during tapping. [ABSTRACT FROM AUTHOR]

Pea fiber concentrate (PFC) and wheat fiber concentrate (WFC) were used as dietary fibers in beef burger formulation. These fibers were characterized in terms of chemical composition and techno-functional properties. WFC and PFC presented similar water-binding capacity (3.12 g/g and 3.07 g/g, respectively), whereas a higher oil-binding capacity was observed for WFC (2.89 g/g versus 1.74 g/g). In this study, the level of PFC was fixed at 0.5%, whereas different levels of WFC (0.5%, 1% and 1.5%) were tested. The water-holding capacity of raw beef burger was significantly higher with the addition of fibers. The use of these dietary fibers in beef burger formulation improves their cooking properties, i.e., increases the cooking yield and decreases the shrinkage, and minimizes production cost without degradation of sensory properties. PRACTICAL APPLICATIONS The use of dietary fiber and water for meat replacement in beef burger formulation was investigated in order to reduce production costs and to improve nutritional characteristics and cooking properties of beef burgers without affecting sensory properties. [ABSTRACT FROM AUTHOR]

In the present study, the nutritional and functional components of fresh and roasted sweet potatoes from 11 cultivars were determined. Results showed that the fresh and roasted sweet potatoes were both rich in protein (3.54–10.34 g/100 g) and dietary fiber (1.81–8.66 g/100 g), with low gross energy (1,576.12–1,638.94 kJ/100 g) and fat (0.75–1.09 g/100 g). After roasting, starch (from 59.46 to 54.43 g/100 g) and protein (from 8.77 to 7.90 g/100 g) contents decreased, while total polyphenol content (from 7.46 to 10.74 mg CHAE/g) and antioxidant activity (from 2.42 to 2.72 μg TE/mg) increased. In addition, most vitamins are preserved after roasting. Gray relational analysis suggested that Yanshu No.25 exhibited the best comprehensive nutritional values (with a weighted gray correlative degree of 0.7787), followed by Longshu No.9 (0.7356). The above results could provide some data support for the research and development, and commercial production of roasted sweet potato with stable high quality. Chemical compounds studied in this article: Chlorogenic acid (PubChem CID:1794427); sulfuric acid (PubChem CID:1118); acetonitrile (PubChem CID:6342); disodium hydrogen phosphate (PubChem CID:24203); acetic acid (PubChem CID:176); sodium hydroxide (PubChem CID:14798); hydrochloric acid (PubChem CID:313); alpha‐D‐glucose (PubChem CID:79025); sodium carbonate (PubChem CID:10340); and ethanol (PubChem CID:702). Practical applications: Roasted sweet potato has become a popular product for consumers because it is famous for its excellence in color, aroma, and taste. As roasted sweet potatoes are mainly processed in small workshops, without considering the cultivar issue, the quality of roasted sweet potato products could not be guaranteed, which have caused a large loss of consumers. So far, there is little information on the analysis of different sweet potato cultivars, especially the effects of roasting on the changes in nutritional qualities of different cultivars. The results of this study could provide some data support for the research and development, and commercial production of roasted sweet potato with stable high quality, which could further promote the healthy development of roasted sweet potato industry. [ABSTRACT FROM AUTHOR]